NASA Technical Reports Server (NTRS) 20120003877: The SPoRT-WRF: Evaluating the Impact of NASA Datasets on Convective Forecasts

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by  NASA Technical Reports Server (NTRS)

The SPoRT-WRF: Evaluating the Impact of NASA Datasets on Convective Forecasts

Bradley Zavodsky1, Jonathan Case2, Danielle Kozlowski3, Andrew Molthan1
1NASA Marshall Space Flight Center, Huntsville, AL
2ENSCO, Inc., Huntsville, AL
3University of Missouri, Columbia, MO

The Short-term Prediction Research and Transition Center (SPoRT) is a collaborative
partnership between NASA and operational forecasting entities, including a number of National
Weather Service offices. SPoRT transitions real-time NASA products and capabilities to its
partners to address specific operational forecast challenges. One challenge that forecasters face is
applying convection-allowing numerical models to predict mesoscale convective weather. In
order to address this specific forecast challenge, SPoRT produces real-time mesoscale model
forecasts using the Weather Research and Forecasting (WRF) model that includes unique NASA
products and capabilities. Currently, the SPoRT configuration of the WRF model (SPoRT-
WRF) incorporates the 4-km Land Information System (LIS) land surface data, 1-km SPoRT sea
surface temperature analysis and 1-km Moderate resolution Imaging Spectroradiometer
(MODIS) greenness vegetation fraction (GVF) analysis, and retrieved thermodynamic profiles
from the Atmospheric Infrared Sounder (AIRS). The LIS, SST, and GVF data are all integrated
into the SPoRT-WRF through adjustments to the initial and boundary conditions, and the AIRS
data are assimilated into a 9-hour SPoRT WRF forecast each day at 0900 UTC. This study
dissects the overall impact of the NASA datasets and the individual surface and atmospheric
component datasets on daily mesoscale forecasts.

A case study covering the super tornado outbreak across the Central and Southeastern United
States during 25-27 April 2011 is examined. Three different forecasts are analyzed including the
SPoRT-WRF (NASA surface and atmospheric data), the SPoRT WRF without AIRS (NASA
surface data only), and the operational National Severe Storms Laboratory (NSSL) WRF (control
with no NASA data). The forecasts are compared qualitatively by examining simulated versus
observed radar reflectivity. Differences between the simulated reflectivity are further
investigated using convective parameters along with model soundings to determine the impacts
of the various NASA datasets. Additionally, quantitative evaluation of select meteorological
parameters is performed using the Meteorological Evaluation Tools model verification package
to compare forecasts to in situ surface and upper air observations.

To be presented at: 16th Symposium on Integrating and Assimilation Systems for the
Atmosphere, Oceans, and Land Surface (IOAS-AOLS) at the 92nd Annual American
Meteorological Society Meeting in New Orleans, LA, 22-26 January 2012.